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From: PJ Weisberg <pj@irregularexpressions.net>
To: Angelo Borsotti <angelo.borsotti@gmail.com>
Cc: Junio C Hamano <gitster@pobox.com>,
	Johannes Sixt <j.sixt@viscovery.net>, git <git@vger.kernel.org>
Subject: Re: erratic behavior commit --allow-empty
Date: Tue, 2 Oct 2012 19:10:01 -0700	[thread overview]
Message-ID: <CAJsNXTm9ADZv4SbabAR_WzGrZO8wDjvk+9Lsis0STHGo1EhqwQ@mail.gmail.com> (raw)
In-Reply-To: <CAB9Jk9D-eJ8goYx7LWqGcWcLgRDS8+qLZVUsvvJ+QOtryP9-zg@mail.gmail.com>

On Tue, Oct 2, 2012 at 2:56 PM, Angelo Borsotti
<angelo.borsotti@gmail.com> wrote:
> Hi Junio,
>
>> It does create one; it just is the same one you already happen to have,
>> when you record the same state on top of the same history as the
>> same person at the same time.
>>
>
> No, it does not create one: as you can see from the trace of the execution
> of my script, the sha of the commit is the same as that of the other,
> which means
> that in the .git/objects there is only one such commit object, and not two with
> the same sha. The meaning of the word "create" is to bring into being something
> that did not exist before. There is no "creation" if the object already exists.

It's also impossible to create two identical files in Git.  If you
try, you'll find that they both have the same SHA1, and thus are
represented by the same object in .git/objects.

You have a script that creates two commits that are identical in every
way.  What practical difference does it make whether they're
represented by one object or two?

-PJ

Gehm's Corollary to Clark's Law: Any technology distinguishable from
magic is insufficiently advanced.

  reply	other threads:[~2012-10-03  2:10 UTC|newest]

Thread overview: 53+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-10-02  7:51 erratic behavior commit --allow-empty Angelo Borsotti
2012-10-02  8:26 ` Johannes Sixt
2012-10-02  8:49   ` Angelo Borsotti
2012-10-02 17:27   ` Junio C Hamano
2012-10-02 19:34     ` Angelo Borsotti
2012-10-02 19:56       ` Junio C Hamano
2012-10-02 21:56         ` Angelo Borsotti
2012-10-03  2:10           ` PJ Weisberg [this message]
2012-10-03  5:37           ` Johannes Sixt
2012-10-03  6:22             ` Angelo Borsotti
2012-10-03  6:27               ` Johannes Sixt
     [not found]                 ` <CAB9Jk9AgtNQfWDr31CWbXf2ag=11du-aruu-0+nOZ3KaaG9=og@mail.gmail.com>
2012-10-03  7:12                   ` Johannes Sixt
2012-10-03  7:35                     ` Angelo Borsotti
2012-10-03 20:49                     ` Junio C Hamano
2012-10-03  7:29           ` Philip Oakley
2012-10-03  7:45             ` Angelo Borsotti
2012-10-03  8:04               ` Matthieu Moy
2012-10-03  8:24                 ` Angelo Borsotti
2012-10-03 11:07                   ` Matthieu Moy
2012-10-03 11:52                     ` Angelo Borsotti
     [not found]                       ` <CABURp0oHez6j8+FPG8Zm52TGVyC1XwWhE55TBDrXRGFrW6kWww@mail.gmail.com>
2012-10-03 13:35                         ` Angelo Borsotti
2012-10-03 14:15                           ` Phil Hord
2012-10-03 13:57                       ` Matthieu Moy
2012-10-03 14:46                         ` Angelo Borsotti
2012-10-03 14:52                           ` Matthieu Moy
2012-10-03 22:32                       ` Philip Oakley
2012-10-04  7:07                         ` Angelo Borsotti
2012-10-04 13:24                           ` Phil Hord
2012-10-04 19:00                             ` Angelo Borsotti
2012-10-04 21:17                           ` Philip Oakley
2012-10-04 22:09                             ` Angelo Borsotti
2012-10-04 22:42                               ` Philip Oakley
2012-10-04 23:10                                 ` Angelo Borsotti
2012-10-03 12:25                   ` Tomas Carnecky
2012-10-03 13:08                     ` Angelo Borsotti
2012-10-03 10:12               ` Andreas Schwab
2012-10-03 11:37                 ` Angelo Borsotti
2012-10-03 13:44                   ` Andreas Schwab
2012-10-03 14:37                     ` Angelo Borsotti
2012-10-03 16:44                       ` Andreas Schwab
2012-10-03 17:37                         ` Angelo Borsotti
2012-10-03 19:03                           ` Andreas Schwab
2012-10-03 19:11                             ` Angelo Borsotti
2012-10-03 20:30                               ` Andreas Schwab
2012-10-03 12:59       ` Phil Hord
2012-10-03 14:25         ` Angelo Borsotti
2012-10-03 16:06           ` PJ Weisberg
2012-10-03 17:34             ` Angelo Borsotti
2012-10-03 19:05               ` Andreas Schwab
2012-10-03 19:43               ` PJ Weisberg
2012-10-05  8:15               ` Lars Noschinski
2013-01-12 18:30   ` Jan Engelhardt
2013-01-16 12:26     ` Joachim Schmitz

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